Rock-drilling apparatus



April 6, 1929. A. H. SKAER ET AL 1,708,976

' nocx DRILLING APPARATUS Filed Feb. 25, 1926 I 2 Sheets-Sheet 1 April 1929. A. H. SKAER ET AL 1,708,976

ROCK DRILLING APPARATUS Filed Feb. 25, 1926 2 Sheets-Sheet 2 gin-001N006 Patented Apr. 16, 1929.

UNITED STATES 1,708,976 PATENT OFFICE.

ARTHUR H. SKAER AND AUGUST H. KATTERJOHN, OF DENVER, COLORADO, ASSIGIF ORS, BY MESNE ASSIGNMENTS, TO THE GARDNER-DENVER COMPANY, OF QUINCY, ILLINOIS, A CORPORATION OF DELAWARE. 7

ROCK-DRILLING APPARATUS.

Application filed. February 25, 1926. Serial K9. 90,595.

The present invention relates to rock drilling apparatus, and the object is to provide novel means for more completely discharging the cuttings and detritus from the holes being drilled.

In the accompanying drawings Figure 1 is a vertical longitudinal sectional view through a preferred embodiment of the invention,

Figure 2 is a vertical sectional view on an enlarged scale through the portion of the apparatus containing the novel mechanism,

Figure 3 is a cross sectional view on the line 33 of Figure 2,

Figure 4 is, a sectional view taken on the line 4-4. of Figure 2.

In the form of structure shown, a guide shell 5 has slidably mounted thereon the drilling apparatus. This apparatus consists of a cylinder member 6 provided with a iston head chamber 7. In the front en of the cylinder member is located a rotary chuck 8 having a hammer extension chamber 9. This chuck is provided with suitable means for holding a drill steel 10 with the rear end extending into the chamber 9, the drill steel having the usual longitudinal bore 11 therethrough.

A reciprocatory piston comprises a head 12 that operates in the piston head chamber 7 and a hammer extension 13 that operates in the chamber 9, and is adapted to strike the rear end of the steel 10 on the reciprocation of the piston. The hammer extension 13 is provided with longitudinal grooves or keyways 14, in which are engaged the flutes 15 of the chuck 8, so that said piston and chuck will rotate together, while the piston can reciprocate with respect to the chuck in order to deliver the hammer blows against the drill steel 10.

Located in the rear end of the cylinder member 6, is a sleeve 16 surrounded by a valve casing 17. An automatic reciprocatory valve 18 in the casing 17 and surrounding the sleeve 16, serves to control the supply of motive fluid to the chamber 7 on opposite sides of the head 12 in order to effect the reciprocation of the hammer piston. Any suitable valve mechanism may be employed for this purpose. Motive fiuid is supplied to the valve chamber through a throttle valve 19 that controls the supply to a port 20.

Rotatably mounted in the sleeve 16 is a rifle bar 21, the flutes of which are engaged with the nut 22 secured in the rear end of the hammer piston 12-13. The rear end of this rifle bar is provided with a head 23 carrying a plurality of spring-pressed pawls 24 that engage teeth 25 formed internally in a ratchet ring 26 secured in the rear end of the cylinder member 6. The supply port 20 communicates with an annular groove 27 formed in the rear head of the cylinder member, and this annular groove is in communication with the chamber in which the head 23 of the rifle bar 21 rotates as shown in Figure 1. I

The hammer piston 1213 is provided in its rear end with a central longitudinally disposed socket 28 for the reception of the front end of the rifle bar, and the hammer extension 13 is provided in advance of the socket 28 with a plunger chamber 29, the rear portion 30 of which is reduced in size, and preferably ground to a smooth finish. The rifle bar 21 is'provided on its front end with a plunger extension 31 having a ground external diameter that has a substantially leak-proof fit with the portion 30, the extension 31 entering and withdrawing from the plunger chamber 29 as the piston reciprocates. The front end of the hammer extension is furthermore provided with an outlet port 32 that is in line with the bore 11 of a drill steel 10 placed in the chuck, this port 32 being also in constant communication with the hammer extension chamber 9. The rifle bar 21 and plunger extension 31 are also provided with a longitudinal passageway 33 opening into the plunger chamber 29, and at its rear end having communication through the radial ports 34 of the rifle bar head 23, with the chamber in which said head rotates and consequently with the motive fluid supply channel 27.

The usual liquid conducting tube is shown at 35, and extends from the rear head of the cylinder member through the passageway 33, the plunger chamber 29, and the port 32, into the hammer extension chamber 9 so that it will enter the rear end of the bore 11 in the drill steel 10. It will be noted that this tube 35 is of considerably less diameter than the passageway 33 so that motive fluid can flow freely through the passageway aroundthe tube.

With this construction the plunger chamber 29 and the plunger 31 operating therein act in the nature of a pump that delivers the motive fluid into the hammer extension chamber 9, and thence into the bore 11 of the drill steel. This has been found to secure a' peculiarly eflective cleansing action in the drill hole that greatly surpasses the ordinary flow of fluid, as heretofore secured. It will be evident that air or motive fluid is being constantly supplied through the passageway 33 into the chamber 29, so that said chamber is'constantly filled with air under pressure. This is true on the forward stroke of the'piston, for the air being under line 'pressure tills the chamber 29 as it is enlarged during such forward stroke. On the return movement little or no air will be forced rearwardly through the passageway because of the line pressure therein. Consequently the plunger will expel the air through the port 32. Just what action takes place at' this point is not entirely clear, but it would appear that the rearward movement of the piston extension 13 in the chamber 9 ordinarily causes a partial vacuum insaid chamber, which in this case is obviated by the air expelled from the chamber 29. Consequently when the piston makes .its succeeding forward stroke, the air that has passed from the chamber 29 into the chamher 9 is now expelled through the bore '11 of the drill steel to the bottom of the hole under sufficient pressuieto secure an effective blowing out or cleansing action.

From the foregoing, it is thought that the construction, operation and many advantages of the herein described inventionwill be apparent to those skilled in the art, without further description, and it will be understood that various changes in the size, shape, proportion andminor details of construction may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention. I

What we claim, is:

1. In a rock drill, the combination with a cylinder member and a piston member op erating therein, of a chuck for holding a drill steel to' be operated on by the piston, sa1d piston having a rifle bar receiving socket and a plunger chamber in advance of the socket and having communication with the bore of a steel engaged'in the chuck, a mile bar engaged with the piston and 0 eratmg in the socket and terminating s ort of the plunger chamber \when the piston is 1n 1ts rearmost position, a pump plunger projecting from the front end of the rifle bar and operating in the plunger chamber, and means for. admitting fluid to the plunger chamber.

2. Ina rockdrill, the combination with a cylinder member and a piston member operating therein, of a chuck for holding a drill piston and operating in the socket, a pump plunger pro1ecting from the rifle bar and of less diameter than the same, said plunger operating in the plunger chamber, and means for admitting fluid to said plunger chamber.

3. In a rock drill, the combination with a cylinder member and a piston member operating therein, of a chuck for holding a drill steel to be operated on by the piston, said piston having a rifle bar receiving socket and a plunger chamber in advance of the socket and having communication with the bore of a steel engaged in the chuck, said plunger chamber having a reduced rear end that is of less diameter than the socket, a rifle bar engaged with the piston and operating in the socket, a pump plunger projecting from the rifle bar and of less diameter than the same and having a sliding fit with the walls of the reduced rear end of said plunger chamber, and means for admitting fluid to said plunger chamber.

4. In a rock drill, the combination with a cylinder member having a piston chamber and a chuck for holding a drill steel, of a piston in the piston chamber for operating on.a drill steel in the chuck, said piston having a plunger chamber provided with a port that communicates with the bore of the steel, a liquid conducting tube extending from the rear end of the cylinder member through the plunger chamber and port for delivering liquid to the bore of the steel, a plunger having a sliding fit in the plunger chamber and having a passageway through which the tube loosely passes, and means for delivering fluid to the passageway, said passageway delivering the fluid to the chamber.

5. In a rock drill, the combination with a c linder member having a iston chamber an a chuck for holding a rill steel, of a piston in the piston chamber for operating on a drill steel in the chuck, said piston having a rifle bar receiving socket in its rear portion, and a plunger chamber in advance of the socket, a rifle bar mounted in the rear end of the cylinder member and operating in the socket; said rifle bar having a ump plunger projecting from its front en and operating in the plunger chamber, said rifle bar and plunger having a passageway therethrough, a liquid conducting tube mounted in the rear end of the cylinder member in rear of the rifle bar mounting and extending through the passageway, said tube being of less cross sectional area than the passageway, and means for delivering fluid to the passageway, said passageway conducting the fluid to-the plunger chamber in advance of the pump plunger.

6. In a rock drill, the combination with a cylinder member having a piston chamber and a ratchet chamber in rear thereof, of a piston operating in the piston chamber and having a plunger chamber, a rotatable rifle bar having ratchet mechanism in the ratchet chamber and having a, pump plunger portion operating in the plunger chamber, said rifle bar having a passageway therethrough in communication with the ratchet chamber and the plunger chamber, and means for delivering fluid to the ratchet chamber for conduction through the passageway to the plunger chamber, said plunger chamber having an outlet port that communicates with the bore of a drill steel operated on by the piston.

7. In a rock drill, the combination with a cylinder member having a piston chamber, and a ratchet chamber in rear thereof, of a piston operating in the piston chamber and having a plunger chamber, a rotatable rifle bar having ratchet mechanism including a head in the ratchet chamber and having a pump plunger portion operating in the plunger chamber, said rifle bar having a passageway therethrough in communication with the plunger chamber and having ports opening through the head into the ratchet chamber, and means for delivering fluid to the ratchet chamber for conduction through the passageway to the plunger chamber, said plunger chamber having an outlet port that" communicates with the bore of a drill steel operated on by the piston.

8. In a rock drill, the combination with a cylinder member having a piston head chamber and a hammer extension chamber in advance thereof, of a piston having a head in the head chamber and a hammer extension that operates in the hammer extension chamher, a chuck for holding a hollow drill steel with its rear end in the hammer extension chamber and in position to be struck by the hammer extension, said piston having a rifle bar socket in its rear end and a plunger chamber in advance of the socket and opening through the front end of the hammer extension, a rifle bar in the socket engaged with the piston and having a plunger extension operating in the plunger chamber and provided with a substantially fluid-tight fit therein, said rifle bar and plunger extension having a passageway therethrough opening into the-plunger chamber and in communication with the motive fluid supply means, and a liquid transmitting tube extending through the passageway, the plunger chamber, and projecting beyond the hammer extension into a position to deliver liquid into the bore of a drill steel, said tube being of less cross sectional area than the passageway to permit the flow of motive fluid therethrough to the plunger chamber.

In testimony whereof, we affix our signatures.

ARTHUR H. SKAER. AUGUST KATTERJQHN. 

